Footwear with pontoon sole structure

ABSTRACT

An article of footwear includes an upper and a sole structure having an outer periphery and one or more pontoons flexibly and resiliently joined to the sole structure. The pontoons are configured to spread laterally when the footwear is loaded to thereby increase the surface area of the sole structure and elastically retract back to an original position when the footwear is unloaded. The increased surface area of the sole reduces sinking of the footwear in soft, loose or saturated ground. Optionally, the sole structure includes paddle blades.

PRIORITY CLAIM

This application claims priority of U.S. Provisional Application Ser. No. 61/778,779, filed Mar. 13, 2013.

FIELD OF THE DISCLOSURE

The present disclosure relates to an article of footwear, and in particular to footwear having a sole structure with pontoons. The footwear of the invention has particular applicability in soft ground, mud, sand and amphibious environments in the outdoor recreation and military fields.

BACKGROUND OF THE DISCLOSURE

Footwear having conventional soles made of resiliently compressible materials is well known in the art. Footwear in general and sole structures in particular has been designed for performance in particular intended environments, i.e., the floor/ground/terrain and other conditions wherein the footwear will be used. Sole structures designed for outdoor activities, such as running, walking, biking and the like, must be durable and provide sufficient support to handle impact forces generated by a wearer during the physical activities. Physical activities performed in soft or loose ground conditions such as mud, sand or snow present particular design challenges. Conventional footwear can sink into soft ground, lose traction, and fail to provide proper adequate support and stability in these conditions.

As a result, there is a need for improved footwear that provides enhanced stability, traction and performance in soft and/or loose ground conditions and in amphibious environments.

SUMMARY OF THE DISCLOSURE

The above-identified need is met by the present footwear incorporating a sole structure having pontoon members. Specifically, one or more pontoons are provided on an outer periphery of the sole. The pontoons are configured and adapted to pivot or otherwise flex outwardly when the footwear is loaded, and elastically retract back to their original position when the footwear is unloaded. More specifically, when the footwear is loaded by running or landing, one or more of the pontoons flex outwardly to provide an increased surface area with the underlying surface, thereby generating greater stability and support. As a result, the increased surface area of the outsole spreads load over a greater area and helps to reduce sinking of the footwear in soft ground. The footwear outsole of the invention is also suitable on hard ground surfaces such a pavement and irregular surfaces such as rocks, roots and the like. The present pontoon sole structure has enhanced resiliency and adaptability to conform to a variety of ground surfaces, namely, soft and hard, wet and dry, smooth and irregular.

Another embodiment of the footwear of the invention includes paddle blades. The blades are particularly advantageous in beach and other amphibious environments. The paddle blades provide increased surface area and dig into the ground, thereby providing enhanced traction, propulsion and control in sand, mud, snow and other loose or saturated materials. Embodiments of the invention include both pontoons and paddle blade traction members.

These and other examples of the present invention are discussed below in the following detailed description of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a first exemplary article of footwear having outsole with pontoons and paddle blades.

FIG. 2 is a bottom plan view of the embodiment of FIG. 1.

FIG. 2A is a cross-sectional view taken along the line 2A-2A of FIG. 2 and in the direction generally indicated.

FIG. 2B is a cross-sectional view taken along the line 2B-2B of FIG. 2 and in the direction generally indicated.

FIG. 3 is a side view of a second exemplary article of footwear having an outsole with pontoons and paddle blades.

FIG. 4 is a bottom plan view of the embodiment of FIG. 3.

FIG. 5 is a side view of a third exemplary article of footwear having an outsole with pontoon members.

FIG. 6 is a cross-sectional view taken along the line 6-6 of FIG. 5 and in the direction generally indicated.

FIG. 7 is a bottom plan view of a fourth exemplary article of footwear in accordance with another embodiment of the present disclosure.

FIG. 8 is a side view of a fifth exemplary article of footwear in accordance with another embodiment of the present disclosure.

FIG. 9 is a bottom plan view of the embodiment of FIG. 8.

FIG. 9A is a cross-sectional view taken along the line 9A-9A of FIG. 9 and in the direction generally indicated.

FIG. 9B is a cross-sectional view taken along the line 9B-9B of FIG. 9 and in the direction generally indicated.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present disclosure is directed to an article of footwear configured to be worn by a user on soft, loose or saturated terrain and/or in amphibious environments. The footwear provides increased surface area to reduce sinking in sand, mud, snow and other loose and/or saturated materials and to provide enhanced traction. Preferred embodiments of the present disclosure are described below by way of example only, with reference to the accompanying drawings.

FIGS. 1 and 2 illustrate an exemplary embodiment of an article of footwear having pontoon members and paddle blades. Footwear 10 includes an upper 20 and a sole structure 30. Generally the upper 20 can be any type of upper, including shoes and boots. The upper 20 can be made of natural materials such as leather, synthetic materials, fabrics, such as a lycra/spandex textile stretch sock, or combinations thereof. The sole structure 30 is preferably wider than the upper, especially in the heel region. The sole structure 30 can be a single layer or plural layers, such as a midsole and outsole 40. The outsole 40 can extend over all or selective portions of an outer surface of the sole structure. The sole structure 30 preferably includes tread members 50 and pontoons 60.

Tread members 50 may include different configurations to provide traction on a variety of surfaces. More specifically, the tread members can include ribs, grooves, lugs, paddles, fins and the like in patterns designed for particular surfaces and environments. For example, in a trail running embodiment, the tread members 50 may comprise knobby lugs, like a motocross tire. In a snow/winter embodiment, the tread members 50 may include a rugged pattern of ribs and grooves to improve footing and traction in snow and ice. In amphibious environments, paddle blades may be provided as explained in greater detail below. The tread members 50 may include a forefoot tread member 78 and a heel tread member 80, which may have similar or different configurations.

In the embodiment of FIGS. 1-2, a forefoot tread member 78 preferably includes paddle blades 90 that project from the bottom of the outsole 40, wrapping around the side edges of the sole. Further, optional blades can be provided on the side portions of the sole wrapping up onto the upper 20 as shown in FIG. 1. The blades 90 are configured to dig into soft ground, thus providing enhanced traction in sand, mud, snow and other loose and/or saturated materials. The paddle blades 90 can be, among other shapes, “V” or fish-bone shaped as shown. The blades 90 can have varying heights, spacing, profiles and other configurations consistent with the object of developing traction in soft, loose and/or saturated ground.

The sole structure 30 further includes shallow grooves 100 spaced between and parallel to the edges of the paddle blades, and deep grooves 110 that extend deeper into the sole 30 than the shallow grooves 100. The grooves 100, 110 form channels for escape of excessive water, snow, mud, and the like from the underlying surface. The shape and layout of the shallow and deep grooves 100, 110 can vary depending on the intended terrain and other environmental conditions.

In the embodiment of FIGS. 1-2, a heel portion of the outsole includes a different tread member 80 having a diamond-shaped knurling pattern to provide traction during walking or running on smooth surfaces such as decks, piers, walkways and the like under potentially slippery conditions. The knurling pattern may be a regular or irregular, constant or varying pattern of protuberances, bumps, raised lines or any similar raised features on any areas of the outsole 40; including for example heel 82 and front toe 84 areas.

The sole structure further includes pontoons 60. Pontoons 60 can be separate from the outsole, or integral with the outsole. The pontoons can also be formed with the midsole. Optionally, an outsole can be secured to the pontoons or a portion thereof. One or more pontoons 60 are located on the outer periphery of the sole structure. The pontoons may be continuous around the periphery, or may be segmented as shown in FIG. 2. The pontoons are compressible, flexible and resilient. Accordingly, the pontoons 60 are configured to pivot and/or spread laterally when the footwear 10 is loaded and elastically retract back to their original shape when the footwear 10 is unloaded. In particular, in one embodiment, the pontoons are hollow tube-like members that are co-molded with or otherwise attached to the outer periphery of the sole structure 30.

FIGS. 2A and 2B illustrate pontoons 60 separated from a central portion 66 of the sole structure by the deep grooves 110. The thickness (T₁) of the outsole and corresponding dimensions of the pontoons in the forefoot (FIG. 2A) is smaller than the thickness (T₂) of the heel region (FIG. 2B). However, in other, zero slope embodiments, the forefoot and heel regions can have similar thicknesses. Grooves 110 extend deeply into the sole leaving a comparatively thin portion of the sole structure connecting pontoons 60 to the central portion 66 of the sole structure 30. The connecting portions function as hinge members 68 to allow the pontoons 60 to pivot, swing or deflect outwardly when the sole structure is under load. The degree of pivot depends on the amount of load, the thickness of the hinge material, the physical properties of the materials and other factors. The thickness (T₃) of the hinge member 68 between an inner surface 64 of the sole structure 30 and the grooves 110 is preferably not less than 7 mm, but could be less depending on the tear strength of the material. The thickness (T₃) can be adjusted depending on the density, resiliency, and tear strength of the sole material(s), the desired amount of pivot, and the desired responsiveness of retraction/rebound when the load is removed. Thickness (T₃) can be substantially constant as shown or can vary from forefoot to heel and from the lateral side to the medial side. Specifically, in some embodiments it may be desirable to provide a thinner or more flexible hinge member 68 on the lateral side while allowing less flexibility and hence more stability on the medial side in the forefoot region.

At rest condition the lower or outer portions of the sole structure extend outwardly beyond the upper to enlarge the surface area of the footwear as shown if FIGS. 2A and 2B. Further, when load is applied to the sole structure, e.g., by running or landing, one or more of the pontoons pivot or flex outwardly to provide an increased surface area with the underlying surface, thereby generating greater stability and support. Further, the increased surface area of the sole structure 30, generated by laterally spreading the pontoons 60 during impact, also helps to reduce sinking of the footwear in soft underlying surfaces, such as sand, mud or snow, i.e., a snow shoe effect.

The sole structure 30 can be comprised of a single material as shown, multiple co-molded materials, layers of different materials that are bonded or laminated together, or combinations thereof. Further, the sole structure can include hollow portions as described below in reference to the embodiment of FIGS. 5-6. In a preferred embodiment, substantially the entire sole structure, including the pontoons, hinge member, central portion and the majority of the outsole are integrally molded of a single material. The material should have sufficient strength, resilience and durability to withstand repeated extension/retraction cycles. Further the material should be sufficiently soft to provide appropriate cushioning and shock absorption. One suitable material is proprietary foam sold under the trade name RMAT having a hardness of between about 40 and 55 durometer. Other natural and synthetic materials can be used, however, based on the desired performance and durability.

Optionally, multiple drainage ports 120 can be disposed in the periphery of the sole structure 30 for escape of water, sand, mud, and the like from the interior of the footwear. Generally, each port can be of any geometric shape, e.g., circular, oval or rectangular. However, in the cases of trail footwear and snow/winter footwear applications, such ports can be omitted.

FIGS. 3 and 4 illustrate another embodiment of the article of footwear having a pontoon sole structure with paddle blades. In this embodiment, substantially the entire outer surface of the sole is equipped with paddle blades 90, which may be suitable for use in marine, surf or other aquatic applications. The “V” configuration of the paddle blades provides traction and propulsion. Additional fins 92 that generally intersect perpendicularly with the paddle blades 90 (e.g., fish-bone shaped) are provided for structural integrity and durability. The paddle blades 90 can be either segmented or undivided. Optionally, paddle blades 94 may extend upwardly on the medial and lateral sidewalls of the sole structure. The height of the blades may be reduced or tapered on the sides as shown in FIG. 3. The blades on the medial and lateral sides and central area are independent of one another being interrupted by the grooves 110. Hence the medial side of the footwear 10 can lift without effecting or leveraging the lateral side of the footwear. Accordingly, in this embodiment, the outsole 40 provides a structure designed to adapt or conform to the ground surface the wearer is walking on.

The footwear 10 of the FIGS. 3-4 embodiment includes optional drainage ports 120 located on the periphery of the sloe structure. Additional, larger drainage ports 130 can be optionally disposed on either or both the medial and lateral sides of the footwear and/or on the bottom of the outsole 40 for water, sand, and/or mud drainage. Ports 130 may be open or more preferably covered with mesh, such as plastic, metal or Kevlar mesh.

As shown in FIG. 4, the outsole comprises a plurality of sectional pontoon members 62 separated by the deep grooves 110. Six pontoon members are shown, but more or less can be used. The pontoon members 62 are arranged in series on the periphery of the sole structure 30. As in the first embodiment, the pontoon members are connected to a central portion 66 of the sole structure with reduced thickness, resilient hinge members. The pontoons 62 are configured to flex outwardly when the footwear is loaded, i.e., the user's foot impacts the ground when running or jumping. The body of the sole structure 30 including the sectional pontoons 62, the resilient hinge member and the central portion 66 are preferably co-molded and integral. The pontoon members are relatively soft, flexible and resilient, whereby they can spread laterally under compression. Optionally, the pontoon members can be hollow. Thereby, the surface area of the footwear is increased by the impact force or the user's weight. The pontoons 60 resiliently retract when unloaded, i.e., when the user lifts his foot from the ground.

The pontoon structure can be substantially continuous around the periphery of the sole structure 30. Preferably, however, the pontoon members 62 are separated by the deep grooves 110. Thereby the pontoon members can articulate independently based on ground conditions and applied loads. Also, the deep grooves 110 provide for the escape of excessive water, snow, mud, and the like on the underlying surface.

FIGS. 5 and 6 schematically illustrate another embodiment of the article of footwear having sectional pontoons 62 secured to the sole structure 30. The pontoons are segmented, tube-like flexible members. Each sectional pontoon 62 is configured to individually flex outwardly when loaded and elastically retract back to its original position when unloaded as indicated by arrows 70 in FIG. 6. FIG. 6 also illustrates how the sloe structure 30 can adjust to uneven ground. First 62 a and second 62 b pontoons are shown. On encountering an object or an uneven surface the first sectional pontoon 62 a can compress and spread under compression in a generally horizontal or lateral direction. As shown graphically (exaggerated) in FIG. 6, the first pontoon 62 a compresses more than the second pontoon 62 b in a form of independent suspension. Upon returning to a flat surface, pontoon 62 a will resiliently return to its original shape and position.

FIG. 7 shows yet another embodiment of the outsole 40 of the invention. The outsole 40 has five sectional pontoons 62 and overlying straps 52. The straps 52 are preferably comprised of a resilient, elastic material and bridge between pontoons 62. Accordingly, the straps 52 are configured to assist in the retraction of the pontoons 62 when the footwear 10 is unloaded. The straps also function as tread members.

FIGS. 8 and 9 illustrate yet another embodiment of the article of footwear having sectional pontoons 62 configured and adapted for obstacle races and other extreme sport events over a variety of terrain including mud. In this embodiment, the outsole 40 includes a plurality of projections or lugs 160, which may be suitable for use in muddy terrain. A quadrilateral (e.g., square-shaped) configuration of the lugs 160 provides traction in the muddy terrain, but the invention is not limited to this configuration. It is preferred that each lug 160 includes a pair of transverse grooves 162 forming a cross-shape on an outer surface of the lug. The transverse grooves 162 improve the resilient grip of the lug on some surfaces. While cross-shaped grooves are shown, other suitable configurations are also contemplated.

The outsole 40 includes one or more pontoons 62 separated by the deep grooves 110. Each pontoon 62 can carry a plurality of lugs 160 as shown in FIG. 9. Grooves 110 are disposed generally parallel to a longitudinal axis L of the outsole 40 around a periphery of the outsole, and the sectional pontoons 62 may be continuous around the periphery of the outsole 40, or may be segmented throughout the outsole. The pontoons 62 are compressible, flexible and resilient as described above relative to the other embodiments. Thus, the pontoons 62 are configured to independently spread laterally when the footwear 10 is loaded and elastically retract back to their original shapes when the footwear 10 is unloaded. Further, as best shown in FIGS. 9A and 9B, the pontoons are joined to central portion 66 of the sole structure by flexible and resilient hinge members 68. The hinge members allow the pontoons to flex outwardly when loaded to provide an increased surface area as shown by arrows 70. This increased surface area of the outsole 40 helps to reduce sinking of the footwear in the muddy terrain.

FIGS. 9A and 9B also illustrate that the forefoot portion (FIG. 9A) of the sole structure is generally thinner than the heel portion (FIG. 9B) and the grooves 110 have different depths based on a specific region of the outsole 40. Each of the sectional pontoons 62 are configured to independently compress and articulate outwardly when loaded and elastically retract back to their original positions when unloaded.

While preferred embodiments of the disclosure have been herein illustrated and described, it is to be appreciated that certain changes, rearrangements and modifications may be made therein without departing from the scope of the disclosure as defined by the appended claims. 

What is claimed is:
 1. An article of footwear comprising: an upper; and a sole structure having an outer periphery attached to the upper, wherein the sole structure comprises one or more pontoons on the outer periphery and joined to the sole structure by one or more flexible and resilient members configured so that the pontoons flex outwardly when the article of footwear is loaded and elastically retract back to an original position when the article of footwear is unloaded.
 2. The article of footwear of claim 1, wherein the one or more flexible and resilient members comprises at least one hinge member connecting the pontoons to a central portion of the sole structure.
 3. The article of footwear as in claim 2, wherein the hinge member is co-molded integrally with the pontoons and the central portion of the sole structure.
 4. The article of footwear as in claim 2, wherein the hinge member is a reduced thickness portion of the sole structure, and the pontoons are separated from the central portion by a deep groove at the hinge member.
 5. The article of footwear as in claim 1, wherein the sole structure includes pontoons on opposed sides of the sole and the flexible and resilient members comprise straps bridging from and between the pontoons on opposed sides.
 6. The article of footwear as in claim 1, where the pontoons are hollow, tube-like members.
 7. The article of footwear of claim 1, wherein the sole structure comprises a plurality of segmented pontoons that individually pivot outwardly and retract back to an original position providing an independent suspension.
 8. The article of footwear of claim 1, wherein the pontoons are arranged substantially continuously around the periphery of the sole structure.
 9. The article of footwear of claim 1, wherein an outer surface of the sole structure comprises a pattern of protuberances for providing traction.
 10. The article of footwear of claim 1, wherein an outer surface of the sole structure includes one or more paddle blades that project from the outer surface of the sole, wrapping around the periphery of the sole structure.
 11. The article of footwear of claim 10, wherein the blades have “V” or fish-bone shaped configuration.
 12. The article of footwear of claim 10, wherein the outer surface of the sole includes one or more fins that generally intersect perpendicularly with the blades.
 13. The article of footwear of claim 1, further comprising a plurality of drainage ports in the upper.
 14. An article of footwear, comprising: an upper; and a sole structure having an outer periphery attached to the upper, wherein the sole structure comprises a central portion and a plurality of segmented pontoons on the outer periphery, the pontoons being joined to the sole structure by one or more flexible and resilient hinge members connecting the pontoons to the central portion of the sole structure, and wherein the hinge members are configured so that the pontoons independently pivot outwardly when the article of footwear is loaded and elastically retract back to an original position when the article of footwear is unloaded.
 15. The article of footwear of claim 14, wherein the central portion of the sole structure, pontoons and hinge member are integrally co-molded.
 16. The article of footwear as in claim 14 wherein the pontoon members and central potion are separated by deep grooves.
 17. The article of footwear of claim 14, wherein the outsole has heel and forefoot portions and the heel portion is thicker.
 18. An article of footwear, comprising: an upper; a sole structure having an outer periphery attached to the upper; wherein the sole structure comprises a central portion and a plurality of segmented pontoons on the outer periphery, the pontoons being joined to the sole structure by one or more flexible and resilient hinge members connecting the pontoons to the central portion of the sole structure, and wherein the one or more hinge members are configured so that the pontoons independently pivot outwardly when the article of footwear is loaded and elastically retract back to an original position when the article of footwear is unloaded; wherein the sole structure including the central portion, pontoons and hinge members are integrally co-molded; and wherein the sole structure further comprises an outsole having a plurality of lugs. 